Add the user to the Admin group under the Users section in the admin control panel. As far as adding a new user, you would have to go through the registration process as there is no selection at this time to manually add one.
"I know I've seen some features that [Name Removed] has refused to incorporate and that should bring quite a few people over to here in order to switch. The user control panel is MUCH more user friendly than anything else I've seen or use."